1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCIe driver for Marvell Armada 370 and Armada XP SoCs
4 *
5 * Author: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/pci.h>
11#include <linux/bitfield.h>
12#include <linux/clk.h>
13#include <linux/delay.h>
14#include <linux/gpio/consumer.h>
15#include <linux/init.h>
16#include <linux/irqchip/chained_irq.h>
17#include <linux/irqdomain.h>
18#include <linux/mbus.h>
19#include <linux/slab.h>
20#include <linux/platform_device.h>
21#include <linux/of_address.h>
22#include <linux/of_irq.h>
23#include <linux/of_pci.h>
24#include <linux/of_platform.h>
25
26#include "../pci.h"
27#include "../pci-bridge-emul.h"
28
29/*
30 * PCIe unit register offsets.
31 */
32#define PCIE_DEV_ID_OFF		0x0000
33#define PCIE_CMD_OFF		0x0004
34#define PCIE_DEV_REV_OFF	0x0008
35#define PCIE_BAR_LO_OFF(n)	(0x0010 + ((n) << 3))
36#define PCIE_BAR_HI_OFF(n)	(0x0014 + ((n) << 3))
37#define PCIE_SSDEV_ID_OFF	0x002c
38#define PCIE_CAP_PCIEXP		0x0060
39#define PCIE_CAP_PCIERR_OFF	0x0100
40#define PCIE_BAR_CTRL_OFF(n)	(0x1804 + (((n) - 1) * 4))
41#define PCIE_WIN04_CTRL_OFF(n)	(0x1820 + ((n) << 4))
42#define PCIE_WIN04_BASE_OFF(n)	(0x1824 + ((n) << 4))
43#define PCIE_WIN04_REMAP_OFF(n)	(0x182c + ((n) << 4))
44#define PCIE_WIN5_CTRL_OFF	0x1880
45#define PCIE_WIN5_BASE_OFF	0x1884
46#define PCIE_WIN5_REMAP_OFF	0x188c
47#define PCIE_CONF_ADDR_OFF	0x18f8
48#define  PCIE_CONF_ADDR_EN		0x80000000
49#define  PCIE_CONF_REG(r)		((((r) & 0xf00) << 16) | ((r) & 0xfc))
50#define  PCIE_CONF_BUS(b)		(((b) & 0xff) << 16)
51#define  PCIE_CONF_DEV(d)		(((d) & 0x1f) << 11)
52#define  PCIE_CONF_FUNC(f)		(((f) & 0x7) << 8)
53#define  PCIE_CONF_ADDR(bus, devfn, where) \
54	(PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn))    | \
55	 PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where) | \
56	 PCIE_CONF_ADDR_EN)
57#define PCIE_CONF_DATA_OFF	0x18fc
58#define PCIE_INT_CAUSE_OFF	0x1900
59#define PCIE_INT_UNMASK_OFF	0x1910
60#define  PCIE_INT_INTX(i)		BIT(24+i)
61#define  PCIE_INT_PM_PME		BIT(28)
62#define  PCIE_INT_ALL_MASK		GENMASK(31, 0)
63#define PCIE_CTRL_OFF		0x1a00
64#define  PCIE_CTRL_X1_MODE		0x0001
65#define  PCIE_CTRL_RC_MODE		BIT(1)
66#define  PCIE_CTRL_MASTER_HOT_RESET	BIT(24)
67#define PCIE_STAT_OFF		0x1a04
68#define  PCIE_STAT_BUS                  0xff00
69#define  PCIE_STAT_DEV                  0x1f0000
70#define  PCIE_STAT_LINK_DOWN		BIT(0)
71#define PCIE_SSPL_OFF		0x1a0c
72#define  PCIE_SSPL_VALUE_SHIFT		0
73#define  PCIE_SSPL_VALUE_MASK		GENMASK(7, 0)
74#define  PCIE_SSPL_SCALE_SHIFT		8
75#define  PCIE_SSPL_SCALE_MASK		GENMASK(9, 8)
76#define  PCIE_SSPL_ENABLE		BIT(16)
77#define PCIE_RC_RTSTA		0x1a14
78#define PCIE_DEBUG_CTRL         0x1a60
79#define  PCIE_DEBUG_SOFT_RESET		BIT(20)
80
81struct mvebu_pcie_port;
82
83/* Structure representing all PCIe interfaces */
84struct mvebu_pcie {
85	struct platform_device *pdev;
86	struct mvebu_pcie_port *ports;
87	struct resource io;
88	struct resource realio;
89	struct resource mem;
90	int nports;
91};
92
93struct mvebu_pcie_window {
94	phys_addr_t base;
95	phys_addr_t remap;
96	size_t size;
97};
98
99/* Structure representing one PCIe interface */
100struct mvebu_pcie_port {
101	char *name;
102	void __iomem *base;
103	u32 port;
104	u32 lane;
105	bool is_x4;
106	int devfn;
107	unsigned int mem_target;
108	unsigned int mem_attr;
109	unsigned int io_target;
110	unsigned int io_attr;
111	struct clk *clk;
112	struct gpio_desc *reset_gpio;
113	char *reset_name;
114	struct pci_bridge_emul bridge;
115	struct device_node *dn;
116	struct mvebu_pcie *pcie;
117	struct mvebu_pcie_window memwin;
118	struct mvebu_pcie_window iowin;
119	u32 saved_pcie_stat;
120	struct resource regs;
121	u8 slot_power_limit_value;
122	u8 slot_power_limit_scale;
123	struct irq_domain *intx_irq_domain;
124	raw_spinlock_t irq_lock;
125	int intx_irq;
126};
127
128static inline void mvebu_writel(struct mvebu_pcie_port *port, u32 val, u32 reg)
129{
130	writel(val, port->base + reg);
131}
132
133static inline u32 mvebu_readl(struct mvebu_pcie_port *port, u32 reg)
134{
135	return readl(port->base + reg);
136}
137
138static inline bool mvebu_has_ioport(struct mvebu_pcie_port *port)
139{
140	return port->io_target != -1 && port->io_attr != -1;
141}
142
143static bool mvebu_pcie_link_up(struct mvebu_pcie_port *port)
144{
145	return !(mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
146}
147
148static u8 mvebu_pcie_get_local_bus_nr(struct mvebu_pcie_port *port)
149{
150	return (mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_BUS) >> 8;
151}
152
153static void mvebu_pcie_set_local_bus_nr(struct mvebu_pcie_port *port, int nr)
154{
155	u32 stat;
156
157	stat = mvebu_readl(port, PCIE_STAT_OFF);
158	stat &= ~PCIE_STAT_BUS;
159	stat |= nr << 8;
160	mvebu_writel(port, stat, PCIE_STAT_OFF);
161}
162
163static void mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port *port, int nr)
164{
165	u32 stat;
166
167	stat = mvebu_readl(port, PCIE_STAT_OFF);
168	stat &= ~PCIE_STAT_DEV;
169	stat |= nr << 16;
170	mvebu_writel(port, stat, PCIE_STAT_OFF);
171}
172
173static void mvebu_pcie_disable_wins(struct mvebu_pcie_port *port)
174{
175	int i;
176
177	mvebu_writel(port, 0, PCIE_BAR_LO_OFF(0));
178	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0));
179
180	for (i = 1; i < 3; i++) {
181		mvebu_writel(port, 0, PCIE_BAR_CTRL_OFF(i));
182		mvebu_writel(port, 0, PCIE_BAR_LO_OFF(i));
183		mvebu_writel(port, 0, PCIE_BAR_HI_OFF(i));
184	}
185
186	for (i = 0; i < 5; i++) {
187		mvebu_writel(port, 0, PCIE_WIN04_CTRL_OFF(i));
188		mvebu_writel(port, 0, PCIE_WIN04_BASE_OFF(i));
189		mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
190	}
191
192	mvebu_writel(port, 0, PCIE_WIN5_CTRL_OFF);
193	mvebu_writel(port, 0, PCIE_WIN5_BASE_OFF);
194	mvebu_writel(port, 0, PCIE_WIN5_REMAP_OFF);
195}
196
197/*
198 * Setup PCIE BARs and Address Decode Wins:
199 * BAR[0] -> internal registers (needed for MSI)
200 * BAR[1] -> covers all DRAM banks
201 * BAR[2] -> Disabled
202 * WIN[0-3] -> DRAM bank[0-3]
203 */
204static void mvebu_pcie_setup_wins(struct mvebu_pcie_port *port)
205{
206	const struct mbus_dram_target_info *dram;
207	u32 size;
208	int i;
209
210	dram = mv_mbus_dram_info();
211
212	/* First, disable and clear BARs and windows. */
213	mvebu_pcie_disable_wins(port);
214
215	/* Setup windows for DDR banks.  Count total DDR size on the fly. */
216	size = 0;
217	for (i = 0; i < dram->num_cs; i++) {
218		const struct mbus_dram_window *cs = dram->cs + i;
219
220		mvebu_writel(port, cs->base & 0xffff0000,
221			     PCIE_WIN04_BASE_OFF(i));
222		mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
223		mvebu_writel(port,
224			     ((cs->size - 1) & 0xffff0000) |
225			     (cs->mbus_attr << 8) |
226			     (dram->mbus_dram_target_id << 4) | 1,
227			     PCIE_WIN04_CTRL_OFF(i));
228
229		size += cs->size;
230	}
231
232	/* Round up 'size' to the nearest power of two. */
233	if ((size & (size - 1)) != 0)
234		size = 1 << fls(size);
235
236	/* Setup BAR[1] to all DRAM banks. */
237	mvebu_writel(port, dram->cs[0].base, PCIE_BAR_LO_OFF(1));
238	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(1));
239	mvebu_writel(port, ((size - 1) & 0xffff0000) | 1,
240		     PCIE_BAR_CTRL_OFF(1));
241
242	/*
243	 * Point BAR[0] to the device's internal registers.
244	 */
245	mvebu_writel(port, round_down(port->regs.start, SZ_1M), PCIE_BAR_LO_OFF(0));
246	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0));
247}
248
249static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port)
250{
251	u32 ctrl, lnkcap, cmd, dev_rev, unmask, sspl;
252
253	/* Setup PCIe controller to Root Complex mode. */
254	ctrl = mvebu_readl(port, PCIE_CTRL_OFF);
255	ctrl |= PCIE_CTRL_RC_MODE;
256	mvebu_writel(port, ctrl, PCIE_CTRL_OFF);
257
258	/*
259	 * Set Maximum Link Width to X1 or X4 in Root Port's PCIe Link
260	 * Capability register. This register is defined by PCIe specification
261	 * as read-only but this mvebu controller has it as read-write and must
262	 * be set to number of SerDes PCIe lanes (1 or 4). If this register is
263	 * not set correctly then link with endpoint card is not established.
264	 */
265	lnkcap = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP);
266	lnkcap &= ~PCI_EXP_LNKCAP_MLW;
267	lnkcap |= FIELD_PREP(PCI_EXP_LNKCAP_MLW, port->is_x4 ? 4 : 1);
268	mvebu_writel(port, lnkcap, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP);
269
270	/* Disable Root Bridge I/O space, memory space and bus mastering. */
271	cmd = mvebu_readl(port, PCIE_CMD_OFF);
272	cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
273	mvebu_writel(port, cmd, PCIE_CMD_OFF);
274
275	/*
276	 * Change Class Code of PCI Bridge device to PCI Bridge (0x6004)
277	 * because default value is Memory controller (0x5080).
278	 *
279	 * Note that this mvebu PCI Bridge does not have compliant Type 1
280	 * Configuration Space. Header Type is reported as Type 0 and it
281	 * has format of Type 0 config space.
282	 *
283	 * Moreover Type 0 BAR registers (ranges 0x10 - 0x28 and 0x30 - 0x34)
284	 * have the same format in Marvell's specification as in PCIe
285	 * specification, but their meaning is totally different and they do
286	 * different things: they are aliased into internal mvebu registers
287	 * (e.g. PCIE_BAR_LO_OFF) and these should not be changed or
288	 * reconfigured by pci device drivers.
289	 *
290	 * Therefore driver uses emulation of PCI Bridge which emulates
291	 * access to configuration space via internal mvebu registers or
292	 * emulated configuration buffer. Driver access these PCI Bridge
293	 * directly for simplification, but these registers can be accessed
294	 * also via standard mvebu way for accessing PCI config space.
295	 */
296	dev_rev = mvebu_readl(port, PCIE_DEV_REV_OFF);
297	dev_rev &= ~0xffffff00;
298	dev_rev |= PCI_CLASS_BRIDGE_PCI_NORMAL << 8;
299	mvebu_writel(port, dev_rev, PCIE_DEV_REV_OFF);
300
301	/* Point PCIe unit MBUS decode windows to DRAM space. */
302	mvebu_pcie_setup_wins(port);
303
304	/*
305	 * Program Root Port to automatically send Set_Slot_Power_Limit
306	 * PCIe Message when changing status from Dl_Down to Dl_Up and valid
307	 * slot power limit was specified.
308	 */
309	sspl = mvebu_readl(port, PCIE_SSPL_OFF);
310	sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE);
311	if (port->slot_power_limit_value) {
312		sspl |= port->slot_power_limit_value << PCIE_SSPL_VALUE_SHIFT;
313		sspl |= port->slot_power_limit_scale << PCIE_SSPL_SCALE_SHIFT;
314		sspl |= PCIE_SSPL_ENABLE;
315	}
316	mvebu_writel(port, sspl, PCIE_SSPL_OFF);
317
318	/* Mask all interrupt sources. */
319	mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF);
320
321	/* Clear all interrupt causes. */
322	mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF);
323
324	/* Check if "intx" interrupt was specified in DT. */
325	if (port->intx_irq > 0)
326		return;
327
328	/*
329	 * Fallback code when "intx" interrupt was not specified in DT:
330	 * Unmask all legacy INTx interrupts as driver does not provide a way
331	 * for masking and unmasking of individual legacy INTx interrupts.
332	 * Legacy INTx are reported via one shared GIC source and therefore
333	 * kernel cannot distinguish which individual legacy INTx was triggered.
334	 * These interrupts are shared, so it should not cause any issue. Just
335	 * performance penalty as every PCIe interrupt handler needs to be
336	 * called when some interrupt is triggered.
337	 */
338	unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
339	unmask |= PCIE_INT_INTX(0) | PCIE_INT_INTX(1) |
340		  PCIE_INT_INTX(2) | PCIE_INT_INTX(3);
341	mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
342}
343
344static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
345						    struct pci_bus *bus,
346						    int devfn);
347
348static int mvebu_pcie_child_rd_conf(struct pci_bus *bus, u32 devfn, int where,
349				    int size, u32 *val)
350{
351	struct mvebu_pcie *pcie = bus->sysdata;
352	struct mvebu_pcie_port *port;
353	void __iomem *conf_data;
354
355	port = mvebu_pcie_find_port(pcie, bus, devfn);
356	if (!port)
357		return PCIBIOS_DEVICE_NOT_FOUND;
358
359	if (!mvebu_pcie_link_up(port))
360		return PCIBIOS_DEVICE_NOT_FOUND;
361
362	conf_data = port->base + PCIE_CONF_DATA_OFF;
363
364	mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
365		     PCIE_CONF_ADDR_OFF);
366
367	switch (size) {
368	case 1:
369		*val = readb_relaxed(conf_data + (where & 3));
370		break;
371	case 2:
372		*val = readw_relaxed(conf_data + (where & 2));
373		break;
374	case 4:
375		*val = readl_relaxed(conf_data);
376		break;
377	default:
378		return PCIBIOS_BAD_REGISTER_NUMBER;
379	}
380
381	return PCIBIOS_SUCCESSFUL;
382}
383
384static int mvebu_pcie_child_wr_conf(struct pci_bus *bus, u32 devfn,
385				    int where, int size, u32 val)
386{
387	struct mvebu_pcie *pcie = bus->sysdata;
388	struct mvebu_pcie_port *port;
389	void __iomem *conf_data;
390
391	port = mvebu_pcie_find_port(pcie, bus, devfn);
392	if (!port)
393		return PCIBIOS_DEVICE_NOT_FOUND;
394
395	if (!mvebu_pcie_link_up(port))
396		return PCIBIOS_DEVICE_NOT_FOUND;
397
398	conf_data = port->base + PCIE_CONF_DATA_OFF;
399
400	mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
401		     PCIE_CONF_ADDR_OFF);
402
403	switch (size) {
404	case 1:
405		writeb(val, conf_data + (where & 3));
406		break;
407	case 2:
408		writew(val, conf_data + (where & 2));
409		break;
410	case 4:
411		writel(val, conf_data);
412		break;
413	default:
414		return PCIBIOS_BAD_REGISTER_NUMBER;
415	}
416
417	return PCIBIOS_SUCCESSFUL;
418}
419
420static struct pci_ops mvebu_pcie_child_ops = {
421	.read = mvebu_pcie_child_rd_conf,
422	.write = mvebu_pcie_child_wr_conf,
423};
424
425/*
426 * Remove windows, starting from the largest ones to the smallest
427 * ones.
428 */
429static void mvebu_pcie_del_windows(struct mvebu_pcie_port *port,
430				   phys_addr_t base, size_t size)
431{
432	while (size) {
433		size_t sz = 1 << (fls(size) - 1);
434
435		mvebu_mbus_del_window(base, sz);
436		base += sz;
437		size -= sz;
438	}
439}
440
441/*
442 * MBus windows can only have a power of two size, but PCI BARs do not
443 * have this constraint. Therefore, we have to split the PCI BAR into
444 * areas each having a power of two size. We start from the largest
445 * one (i.e highest order bit set in the size).
446 */
447static int mvebu_pcie_add_windows(struct mvebu_pcie_port *port,
448				   unsigned int target, unsigned int attribute,
449				   phys_addr_t base, size_t size,
450				   phys_addr_t remap)
451{
452	size_t size_mapped = 0;
453
454	while (size) {
455		size_t sz = 1 << (fls(size) - 1);
456		int ret;
457
458		ret = mvebu_mbus_add_window_remap_by_id(target, attribute, base,
459							sz, remap);
460		if (ret) {
461			phys_addr_t end = base + sz - 1;
462
463			dev_err(&port->pcie->pdev->dev,
464				"Could not create MBus window at [mem %pa-%pa]: %d\n",
465				&base, &end, ret);
466			mvebu_pcie_del_windows(port, base - size_mapped,
467					       size_mapped);
468			return ret;
469		}
470
471		size -= sz;
472		size_mapped += sz;
473		base += sz;
474		if (remap != MVEBU_MBUS_NO_REMAP)
475			remap += sz;
476	}
477
478	return 0;
479}
480
481static int mvebu_pcie_set_window(struct mvebu_pcie_port *port,
482				  unsigned int target, unsigned int attribute,
483				  const struct mvebu_pcie_window *desired,
484				  struct mvebu_pcie_window *cur)
485{
486	int ret;
487
488	if (desired->base == cur->base && desired->remap == cur->remap &&
489	    desired->size == cur->size)
490		return 0;
491
492	if (cur->size != 0) {
493		mvebu_pcie_del_windows(port, cur->base, cur->size);
494		cur->size = 0;
495		cur->base = 0;
496
497		/*
498		 * If something tries to change the window while it is enabled
499		 * the change will not be done atomically. That would be
500		 * difficult to do in the general case.
501		 */
502	}
503
504	if (desired->size == 0)
505		return 0;
506
507	ret = mvebu_pcie_add_windows(port, target, attribute, desired->base,
508				     desired->size, desired->remap);
509	if (ret) {
510		cur->size = 0;
511		cur->base = 0;
512		return ret;
513	}
514
515	*cur = *desired;
516	return 0;
517}
518
519static int mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port)
520{
521	struct mvebu_pcie_window desired = {};
522	struct pci_bridge_emul_conf *conf = &port->bridge.conf;
523
524	/* Are the new iobase/iolimit values invalid? */
525	if (conf->iolimit < conf->iobase ||
526	    le16_to_cpu(conf->iolimitupper) < le16_to_cpu(conf->iobaseupper))
527		return mvebu_pcie_set_window(port, port->io_target, port->io_attr,
528					     &desired, &port->iowin);
529
530	/*
531	 * We read the PCI-to-PCI bridge emulated registers, and
532	 * calculate the base address and size of the address decoding
533	 * window to setup, according to the PCI-to-PCI bridge
534	 * specifications. iobase is the bus address, port->iowin_base
535	 * is the CPU address.
536	 */
537	desired.remap = ((conf->iobase & 0xF0) << 8) |
538			(le16_to_cpu(conf->iobaseupper) << 16);
539	desired.base = port->pcie->io.start + desired.remap;
540	desired.size = ((0xFFF | ((conf->iolimit & 0xF0) << 8) |
541			 (le16_to_cpu(conf->iolimitupper) << 16)) -
542			desired.remap) +
543		       1;
544
545	return mvebu_pcie_set_window(port, port->io_target, port->io_attr, &desired,
546				     &port->iowin);
547}
548
549static int mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port)
550{
551	struct mvebu_pcie_window desired = {.remap = MVEBU_MBUS_NO_REMAP};
552	struct pci_bridge_emul_conf *conf = &port->bridge.conf;
553
554	/* Are the new membase/memlimit values invalid? */
555	if (le16_to_cpu(conf->memlimit) < le16_to_cpu(conf->membase))
556		return mvebu_pcie_set_window(port, port->mem_target, port->mem_attr,
557					     &desired, &port->memwin);
558
559	/*
560	 * We read the PCI-to-PCI bridge emulated registers, and
561	 * calculate the base address and size of the address decoding
562	 * window to setup, according to the PCI-to-PCI bridge
563	 * specifications.
564	 */
565	desired.base = ((le16_to_cpu(conf->membase) & 0xFFF0) << 16);
566	desired.size = (((le16_to_cpu(conf->memlimit) & 0xFFF0) << 16) | 0xFFFFF) -
567		       desired.base + 1;
568
569	return mvebu_pcie_set_window(port, port->mem_target, port->mem_attr, &desired,
570				     &port->memwin);
571}
572
573static pci_bridge_emul_read_status_t
574mvebu_pci_bridge_emul_base_conf_read(struct pci_bridge_emul *bridge,
575				     int reg, u32 *value)
576{
577	struct mvebu_pcie_port *port = bridge->data;
578
579	switch (reg) {
580	case PCI_COMMAND:
581		*value = mvebu_readl(port, PCIE_CMD_OFF);
582		break;
583
584	case PCI_PRIMARY_BUS: {
585		/*
586		 * From the whole 32bit register we support reading from HW only
587		 * secondary bus number which is mvebu local bus number.
588		 * Other bits are retrieved only from emulated config buffer.
589		 */
590		__le32 *cfgspace = (__le32 *)&bridge->conf;
591		u32 val = le32_to_cpu(cfgspace[PCI_PRIMARY_BUS / 4]);
592		val &= ~0xff00;
593		val |= mvebu_pcie_get_local_bus_nr(port) << 8;
594		*value = val;
595		break;
596	}
597
598	case PCI_INTERRUPT_LINE: {
599		/*
600		 * From the whole 32bit register we support reading from HW only
601		 * one bit: PCI_BRIDGE_CTL_BUS_RESET.
602		 * Other bits are retrieved only from emulated config buffer.
603		 */
604		__le32 *cfgspace = (__le32 *)&bridge->conf;
605		u32 val = le32_to_cpu(cfgspace[PCI_INTERRUPT_LINE / 4]);
606		if (mvebu_readl(port, PCIE_CTRL_OFF) & PCIE_CTRL_MASTER_HOT_RESET)
607			val |= PCI_BRIDGE_CTL_BUS_RESET << 16;
608		else
609			val &= ~(PCI_BRIDGE_CTL_BUS_RESET << 16);
610		*value = val;
611		break;
612	}
613
614	default:
615		return PCI_BRIDGE_EMUL_NOT_HANDLED;
616	}
617
618	return PCI_BRIDGE_EMUL_HANDLED;
619}
620
621static pci_bridge_emul_read_status_t
622mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
623				     int reg, u32 *value)
624{
625	struct mvebu_pcie_port *port = bridge->data;
626
627	switch (reg) {
628	case PCI_EXP_DEVCAP:
629		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP);
630		break;
631
632	case PCI_EXP_DEVCTL:
633		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
634		break;
635
636	case PCI_EXP_LNKCAP:
637		/*
638		 * PCIe requires that the Clock Power Management capability bit
639		 * is hard-wired to zero for downstream ports but HW returns 1.
640		 * Additionally enable Data Link Layer Link Active Reporting
641		 * Capable bit as DL_Active indication is provided too.
642		 */
643		*value = (mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP) &
644			  ~PCI_EXP_LNKCAP_CLKPM) | PCI_EXP_LNKCAP_DLLLARC;
645		break;
646
647	case PCI_EXP_LNKCTL:
648		/* DL_Active indication is provided via PCIE_STAT_OFF */
649		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL) |
650			 (mvebu_pcie_link_up(port) ?
651			  (PCI_EXP_LNKSTA_DLLLA << 16) : 0);
652		break;
653
654	case PCI_EXP_SLTCTL: {
655		u16 slotctl = le16_to_cpu(bridge->pcie_conf.slotctl);
656		u16 slotsta = le16_to_cpu(bridge->pcie_conf.slotsta);
657		u32 val = 0;
658		/*
659		 * When slot power limit was not specified in DT then
660		 * ASPL_DISABLE bit is stored only in emulated config space.
661		 * Otherwise reflect status of PCIE_SSPL_ENABLE bit in HW.
662		 */
663		if (!port->slot_power_limit_value)
664			val |= slotctl & PCI_EXP_SLTCTL_ASPL_DISABLE;
665		else if (!(mvebu_readl(port, PCIE_SSPL_OFF) & PCIE_SSPL_ENABLE))
666			val |= PCI_EXP_SLTCTL_ASPL_DISABLE;
667		/* This callback is 32-bit and in high bits is slot status. */
668		val |= slotsta << 16;
669		*value = val;
670		break;
671	}
672
673	case PCI_EXP_RTSTA:
674		*value = mvebu_readl(port, PCIE_RC_RTSTA);
675		break;
676
677	case PCI_EXP_DEVCAP2:
678		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP2);
679		break;
680
681	case PCI_EXP_DEVCTL2:
682		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2);
683		break;
684
685	case PCI_EXP_LNKCTL2:
686		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2);
687		break;
688
689	default:
690		return PCI_BRIDGE_EMUL_NOT_HANDLED;
691	}
692
693	return PCI_BRIDGE_EMUL_HANDLED;
694}
695
696static pci_bridge_emul_read_status_t
697mvebu_pci_bridge_emul_ext_conf_read(struct pci_bridge_emul *bridge,
698				    int reg, u32 *value)
699{
700	struct mvebu_pcie_port *port = bridge->data;
701
702	switch (reg) {
703	case 0:
704	case PCI_ERR_UNCOR_STATUS:
705	case PCI_ERR_UNCOR_MASK:
706	case PCI_ERR_UNCOR_SEVER:
707	case PCI_ERR_COR_STATUS:
708	case PCI_ERR_COR_MASK:
709	case PCI_ERR_CAP:
710	case PCI_ERR_HEADER_LOG+0:
711	case PCI_ERR_HEADER_LOG+4:
712	case PCI_ERR_HEADER_LOG+8:
713	case PCI_ERR_HEADER_LOG+12:
714	case PCI_ERR_ROOT_COMMAND:
715	case PCI_ERR_ROOT_STATUS:
716	case PCI_ERR_ROOT_ERR_SRC:
717		*value = mvebu_readl(port, PCIE_CAP_PCIERR_OFF + reg);
718		break;
719
720	default:
721		return PCI_BRIDGE_EMUL_NOT_HANDLED;
722	}
723
724	return PCI_BRIDGE_EMUL_HANDLED;
725}
726
727static void
728mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge,
729				      int reg, u32 old, u32 new, u32 mask)
730{
731	struct mvebu_pcie_port *port = bridge->data;
732	struct pci_bridge_emul_conf *conf = &bridge->conf;
733
734	switch (reg) {
735	case PCI_COMMAND:
736		mvebu_writel(port, new, PCIE_CMD_OFF);
737		break;
738
739	case PCI_IO_BASE:
740		if ((mask & 0xffff) && mvebu_has_ioport(port) &&
741		    mvebu_pcie_handle_iobase_change(port)) {
742			/* On error disable IO range */
743			conf->iobase &= ~0xf0;
744			conf->iolimit &= ~0xf0;
745			conf->iobase |= 0xf0;
746			conf->iobaseupper = cpu_to_le16(0x0000);
747			conf->iolimitupper = cpu_to_le16(0x0000);
748		}
749		break;
750
751	case PCI_MEMORY_BASE:
752		if (mvebu_pcie_handle_membase_change(port)) {
753			/* On error disable mem range */
754			conf->membase = cpu_to_le16(le16_to_cpu(conf->membase) & ~0xfff0);
755			conf->memlimit = cpu_to_le16(le16_to_cpu(conf->memlimit) & ~0xfff0);
756			conf->membase = cpu_to_le16(le16_to_cpu(conf->membase) | 0xfff0);
757		}
758		break;
759
760	case PCI_IO_BASE_UPPER16:
761		if (mvebu_has_ioport(port) &&
762		    mvebu_pcie_handle_iobase_change(port)) {
763			/* On error disable IO range */
764			conf->iobase &= ~0xf0;
765			conf->iolimit &= ~0xf0;
766			conf->iobase |= 0xf0;
767			conf->iobaseupper = cpu_to_le16(0x0000);
768			conf->iolimitupper = cpu_to_le16(0x0000);
769		}
770		break;
771
772	case PCI_PRIMARY_BUS:
773		if (mask & 0xff00)
774			mvebu_pcie_set_local_bus_nr(port, conf->secondary_bus);
775		break;
776
777	case PCI_INTERRUPT_LINE:
778		if (mask & (PCI_BRIDGE_CTL_BUS_RESET << 16)) {
779			u32 ctrl = mvebu_readl(port, PCIE_CTRL_OFF);
780			if (new & (PCI_BRIDGE_CTL_BUS_RESET << 16))
781				ctrl |= PCIE_CTRL_MASTER_HOT_RESET;
782			else
783				ctrl &= ~PCIE_CTRL_MASTER_HOT_RESET;
784			mvebu_writel(port, ctrl, PCIE_CTRL_OFF);
785		}
786		break;
787
788	default:
789		break;
790	}
791}
792
793static void
794mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
795				      int reg, u32 old, u32 new, u32 mask)
796{
797	struct mvebu_pcie_port *port = bridge->data;
798
799	switch (reg) {
800	case PCI_EXP_DEVCTL:
801		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
802		break;
803
804	case PCI_EXP_LNKCTL:
805		/*
806		 * PCIe requires that the Enable Clock Power Management bit
807		 * is hard-wired to zero for downstream ports but HW allows
808		 * to change it.
809		 */
810		new &= ~PCI_EXP_LNKCTL_CLKREQ_EN;
811
812		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL);
813		break;
814
815	case PCI_EXP_SLTCTL:
816		/*
817		 * Allow to change PCIE_SSPL_ENABLE bit only when slot power
818		 * limit was specified in DT and configured into HW.
819		 */
820		if ((mask & PCI_EXP_SLTCTL_ASPL_DISABLE) &&
821		    port->slot_power_limit_value) {
822			u32 sspl = mvebu_readl(port, PCIE_SSPL_OFF);
823			if (new & PCI_EXP_SLTCTL_ASPL_DISABLE)
824				sspl &= ~PCIE_SSPL_ENABLE;
825			else
826				sspl |= PCIE_SSPL_ENABLE;
827			mvebu_writel(port, sspl, PCIE_SSPL_OFF);
828		}
829		break;
830
831	case PCI_EXP_RTSTA:
832		/*
833		 * PME Status bit in Root Status Register (PCIE_RC_RTSTA)
834		 * is read-only and can be cleared only by writing 0b to the
835		 * Interrupt Cause RW0C register (PCIE_INT_CAUSE_OFF). So
836		 * clear PME via Interrupt Cause.
837		 */
838		if (new & PCI_EXP_RTSTA_PME)
839			mvebu_writel(port, ~PCIE_INT_PM_PME, PCIE_INT_CAUSE_OFF);
840		break;
841
842	case PCI_EXP_DEVCTL2:
843		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2);
844		break;
845
846	case PCI_EXP_LNKCTL2:
847		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2);
848		break;
849
850	default:
851		break;
852	}
853}
854
855static void
856mvebu_pci_bridge_emul_ext_conf_write(struct pci_bridge_emul *bridge,
857				     int reg, u32 old, u32 new, u32 mask)
858{
859	struct mvebu_pcie_port *port = bridge->data;
860
861	switch (reg) {
862	/* These are W1C registers, so clear other bits */
863	case PCI_ERR_UNCOR_STATUS:
864	case PCI_ERR_COR_STATUS:
865	case PCI_ERR_ROOT_STATUS:
866		new &= mask;
867		fallthrough;
868
869	case PCI_ERR_UNCOR_MASK:
870	case PCI_ERR_UNCOR_SEVER:
871	case PCI_ERR_COR_MASK:
872	case PCI_ERR_CAP:
873	case PCI_ERR_HEADER_LOG+0:
874	case PCI_ERR_HEADER_LOG+4:
875	case PCI_ERR_HEADER_LOG+8:
876	case PCI_ERR_HEADER_LOG+12:
877	case PCI_ERR_ROOT_COMMAND:
878	case PCI_ERR_ROOT_ERR_SRC:
879		mvebu_writel(port, new, PCIE_CAP_PCIERR_OFF + reg);
880		break;
881
882	default:
883		break;
884	}
885}
886
887static const struct pci_bridge_emul_ops mvebu_pci_bridge_emul_ops = {
888	.read_base = mvebu_pci_bridge_emul_base_conf_read,
889	.write_base = mvebu_pci_bridge_emul_base_conf_write,
890	.read_pcie = mvebu_pci_bridge_emul_pcie_conf_read,
891	.write_pcie = mvebu_pci_bridge_emul_pcie_conf_write,
892	.read_ext = mvebu_pci_bridge_emul_ext_conf_read,
893	.write_ext = mvebu_pci_bridge_emul_ext_conf_write,
894};
895
896/*
897 * Initialize the configuration space of the PCI-to-PCI bridge
898 * associated with the given PCIe interface.
899 */
900static int mvebu_pci_bridge_emul_init(struct mvebu_pcie_port *port)
901{
902	unsigned int bridge_flags = PCI_BRIDGE_EMUL_NO_PREFMEM_FORWARD;
903	struct pci_bridge_emul *bridge = &port->bridge;
904	u32 dev_id = mvebu_readl(port, PCIE_DEV_ID_OFF);
905	u32 dev_rev = mvebu_readl(port, PCIE_DEV_REV_OFF);
906	u32 ssdev_id = mvebu_readl(port, PCIE_SSDEV_ID_OFF);
907	u32 pcie_cap = mvebu_readl(port, PCIE_CAP_PCIEXP);
908	u8 pcie_cap_ver = ((pcie_cap >> 16) & PCI_EXP_FLAGS_VERS);
909
910	bridge->conf.vendor = cpu_to_le16(dev_id & 0xffff);
911	bridge->conf.device = cpu_to_le16(dev_id >> 16);
912	bridge->conf.class_revision = cpu_to_le32(dev_rev & 0xff);
913
914	if (mvebu_has_ioport(port)) {
915		/* We support 32 bits I/O addressing */
916		bridge->conf.iobase = PCI_IO_RANGE_TYPE_32;
917		bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32;
918	} else {
919		bridge_flags |= PCI_BRIDGE_EMUL_NO_IO_FORWARD;
920	}
921
922	/*
923	 * Older mvebu hardware provides PCIe Capability structure only in
924	 * version 1. New hardware provides it in version 2.
925	 * Enable slot support which is emulated.
926	 */
927	bridge->pcie_conf.cap = cpu_to_le16(pcie_cap_ver | PCI_EXP_FLAGS_SLOT);
928
929	/*
930	 * Set Presence Detect State bit permanently as there is no support for
931	 * unplugging PCIe card from the slot. Assume that PCIe card is always
932	 * connected in slot.
933	 *
934	 * Set physical slot number to port+1 as mvebu ports are indexed from
935	 * zero and zero value is reserved for ports within the same silicon
936	 * as Root Port which is not mvebu case.
937	 *
938	 * Also set correct slot power limit.
939	 */
940	bridge->pcie_conf.slotcap = cpu_to_le32(
941		FIELD_PREP(PCI_EXP_SLTCAP_SPLV, port->slot_power_limit_value) |
942		FIELD_PREP(PCI_EXP_SLTCAP_SPLS, port->slot_power_limit_scale) |
943		FIELD_PREP(PCI_EXP_SLTCAP_PSN, port->port+1));
944	bridge->pcie_conf.slotsta = cpu_to_le16(PCI_EXP_SLTSTA_PDS);
945
946	bridge->subsystem_vendor_id = ssdev_id & 0xffff;
947	bridge->subsystem_id = ssdev_id >> 16;
948	bridge->has_pcie = true;
949	bridge->pcie_start = PCIE_CAP_PCIEXP;
950	bridge->data = port;
951	bridge->ops = &mvebu_pci_bridge_emul_ops;
952
953	return pci_bridge_emul_init(bridge, bridge_flags);
954}
955
956static inline struct mvebu_pcie *sys_to_pcie(struct pci_sys_data *sys)
957{
958	return sys->private_data;
959}
960
961static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
962						    struct pci_bus *bus,
963						    int devfn)
964{
965	int i;
966
967	for (i = 0; i < pcie->nports; i++) {
968		struct mvebu_pcie_port *port = &pcie->ports[i];
969
970		if (!port->base)
971			continue;
972
973		if (bus->number == 0 && port->devfn == devfn)
974			return port;
975		if (bus->number != 0 &&
976		    bus->number >= port->bridge.conf.secondary_bus &&
977		    bus->number <= port->bridge.conf.subordinate_bus)
978			return port;
979	}
980
981	return NULL;
982}
983
984/* PCI configuration space write function */
985static int mvebu_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
986			      int where, int size, u32 val)
987{
988	struct mvebu_pcie *pcie = bus->sysdata;
989	struct mvebu_pcie_port *port;
990
991	port = mvebu_pcie_find_port(pcie, bus, devfn);
992	if (!port)
993		return PCIBIOS_DEVICE_NOT_FOUND;
994
995	return pci_bridge_emul_conf_write(&port->bridge, where, size, val);
996}
997
998/* PCI configuration space read function */
999static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
1000			      int size, u32 *val)
1001{
1002	struct mvebu_pcie *pcie = bus->sysdata;
1003	struct mvebu_pcie_port *port;
1004
1005	port = mvebu_pcie_find_port(pcie, bus, devfn);
1006	if (!port)
1007		return PCIBIOS_DEVICE_NOT_FOUND;
1008
1009	return pci_bridge_emul_conf_read(&port->bridge, where, size, val);
1010}
1011
1012static struct pci_ops mvebu_pcie_ops = {
1013	.read = mvebu_pcie_rd_conf,
1014	.write = mvebu_pcie_wr_conf,
1015};
1016
1017static void mvebu_pcie_intx_irq_mask(struct irq_data *d)
1018{
1019	struct mvebu_pcie_port *port = d->domain->host_data;
1020	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1021	unsigned long flags;
1022	u32 unmask;
1023
1024	raw_spin_lock_irqsave(&port->irq_lock, flags);
1025	unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
1026	unmask &= ~PCIE_INT_INTX(hwirq);
1027	mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
1028	raw_spin_unlock_irqrestore(&port->irq_lock, flags);
1029}
1030
1031static void mvebu_pcie_intx_irq_unmask(struct irq_data *d)
1032{
1033	struct mvebu_pcie_port *port = d->domain->host_data;
1034	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1035	unsigned long flags;
1036	u32 unmask;
1037
1038	raw_spin_lock_irqsave(&port->irq_lock, flags);
1039	unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
1040	unmask |= PCIE_INT_INTX(hwirq);
1041	mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
1042	raw_spin_unlock_irqrestore(&port->irq_lock, flags);
1043}
1044
1045static struct irq_chip intx_irq_chip = {
1046	.name = "mvebu-INTx",
1047	.irq_mask = mvebu_pcie_intx_irq_mask,
1048	.irq_unmask = mvebu_pcie_intx_irq_unmask,
1049};
1050
1051static int mvebu_pcie_intx_irq_map(struct irq_domain *h,
1052				   unsigned int virq, irq_hw_number_t hwirq)
1053{
1054	struct mvebu_pcie_port *port = h->host_data;
1055
1056	irq_set_status_flags(virq, IRQ_LEVEL);
1057	irq_set_chip_and_handler(virq, &intx_irq_chip, handle_level_irq);
1058	irq_set_chip_data(virq, port);
1059
1060	return 0;
1061}
1062
1063static const struct irq_domain_ops mvebu_pcie_intx_irq_domain_ops = {
1064	.map = mvebu_pcie_intx_irq_map,
1065	.xlate = irq_domain_xlate_onecell,
1066};
1067
1068static int mvebu_pcie_init_irq_domain(struct mvebu_pcie_port *port)
1069{
1070	struct device *dev = &port->pcie->pdev->dev;
1071	struct device_node *pcie_intc_node;
1072
1073	raw_spin_lock_init(&port->irq_lock);
1074
1075	pcie_intc_node = of_get_next_child(port->dn, NULL);
1076	if (!pcie_intc_node) {
1077		dev_err(dev, "No PCIe Intc node found for %s\n", port->name);
1078		return -ENODEV;
1079	}
1080
1081	port->intx_irq_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
1082						      &mvebu_pcie_intx_irq_domain_ops,
1083						      port);
1084	of_node_put(pcie_intc_node);
1085	if (!port->intx_irq_domain) {
1086		dev_err(dev, "Failed to get INTx IRQ domain for %s\n", port->name);
1087		return -ENOMEM;
1088	}
1089
1090	return 0;
1091}
1092
1093static void mvebu_pcie_irq_handler(struct irq_desc *desc)
1094{
1095	struct mvebu_pcie_port *port = irq_desc_get_handler_data(desc);
1096	struct irq_chip *chip = irq_desc_get_chip(desc);
1097	struct device *dev = &port->pcie->pdev->dev;
1098	u32 cause, unmask, status;
1099	int i;
1100
1101	chained_irq_enter(chip, desc);
1102
1103	cause = mvebu_readl(port, PCIE_INT_CAUSE_OFF);
1104	unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
1105	status = cause & unmask;
1106
1107	/* Process legacy INTx interrupts */
1108	for (i = 0; i < PCI_NUM_INTX; i++) {
1109		if (!(status & PCIE_INT_INTX(i)))
1110			continue;
1111
1112		if (generic_handle_domain_irq(port->intx_irq_domain, i) == -EINVAL)
1113			dev_err_ratelimited(dev, "unexpected INT%c IRQ\n", (char)i+'A');
1114	}
1115
1116	chained_irq_exit(chip, desc);
1117}
1118
1119static int mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
1120{
1121	/* Interrupt support on mvebu emulated bridges is not implemented yet */
1122	if (dev->bus->number == 0)
1123		return 0; /* Proper return code 0 == NO_IRQ */
1124
1125	return of_irq_parse_and_map_pci(dev, slot, pin);
1126}
1127
1128static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev,
1129						 const struct resource *res,
1130						 resource_size_t start,
1131						 resource_size_t size,
1132						 resource_size_t align)
1133{
1134	if (dev->bus->number != 0)
1135		return start;
1136
1137	/*
1138	 * On the PCI-to-PCI bridge side, the I/O windows must have at
1139	 * least a 64 KB size and the memory windows must have at
1140	 * least a 1 MB size. Moreover, MBus windows need to have a
1141	 * base address aligned on their size, and their size must be
1142	 * a power of two. This means that if the BAR doesn't have a
1143	 * power of two size, several MBus windows will actually be
1144	 * created. We need to ensure that the biggest MBus window
1145	 * (which will be the first one) is aligned on its size, which
1146	 * explains the rounddown_pow_of_two() being done here.
1147	 */
1148	if (res->flags & IORESOURCE_IO)
1149		return round_up(start, max_t(resource_size_t, SZ_64K,
1150					     rounddown_pow_of_two(size)));
1151	else if (res->flags & IORESOURCE_MEM)
1152		return round_up(start, max_t(resource_size_t, SZ_1M,
1153					     rounddown_pow_of_two(size)));
1154	else
1155		return start;
1156}
1157
1158static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev,
1159					      struct device_node *np,
1160					      struct mvebu_pcie_port *port)
1161{
1162	int ret = 0;
1163
1164	ret = of_address_to_resource(np, 0, &port->regs);
1165	if (ret)
1166		return (void __iomem *)ERR_PTR(ret);
1167
1168	return devm_ioremap_resource(&pdev->dev, &port->regs);
1169}
1170
1171#define DT_FLAGS_TO_TYPE(flags)       (((flags) >> 24) & 0x03)
1172#define    DT_TYPE_IO                 0x1
1173#define    DT_TYPE_MEM32              0x2
1174#define DT_CPUADDR_TO_TARGET(cpuaddr) (((cpuaddr) >> 56) & 0xFF)
1175#define DT_CPUADDR_TO_ATTR(cpuaddr)   (((cpuaddr) >> 48) & 0xFF)
1176
1177static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
1178			      unsigned long type,
1179			      unsigned int *tgt,
1180			      unsigned int *attr)
1181{
1182	const int na = 3, ns = 2;
1183	const __be32 *range;
1184	int rlen, nranges, rangesz, pna, i;
1185
1186	*tgt = -1;
1187	*attr = -1;
1188
1189	range = of_get_property(np, "ranges", &rlen);
1190	if (!range)
1191		return -EINVAL;
1192
1193	pna = of_n_addr_cells(np);
1194	rangesz = pna + na + ns;
1195	nranges = rlen / sizeof(__be32) / rangesz;
1196
1197	for (i = 0; i < nranges; i++, range += rangesz) {
1198		u32 flags = of_read_number(range, 1);
1199		u32 slot = of_read_number(range + 1, 1);
1200		u64 cpuaddr = of_read_number(range + na, pna);
1201		unsigned long rtype;
1202
1203		if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_IO)
1204			rtype = IORESOURCE_IO;
1205		else if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_MEM32)
1206			rtype = IORESOURCE_MEM;
1207		else
1208			continue;
1209
1210		if (slot == PCI_SLOT(devfn) && type == rtype) {
1211			*tgt = DT_CPUADDR_TO_TARGET(cpuaddr);
1212			*attr = DT_CPUADDR_TO_ATTR(cpuaddr);
1213			return 0;
1214		}
1215	}
1216
1217	return -ENOENT;
1218}
1219
1220static int mvebu_pcie_suspend(struct device *dev)
1221{
1222	struct mvebu_pcie *pcie;
1223	int i;
1224
1225	pcie = dev_get_drvdata(dev);
1226	for (i = 0; i < pcie->nports; i++) {
1227		struct mvebu_pcie_port *port = pcie->ports + i;
1228		if (!port->base)
1229			continue;
1230		port->saved_pcie_stat = mvebu_readl(port, PCIE_STAT_OFF);
1231	}
1232
1233	return 0;
1234}
1235
1236static int mvebu_pcie_resume(struct device *dev)
1237{
1238	struct mvebu_pcie *pcie;
1239	int i;
1240
1241	pcie = dev_get_drvdata(dev);
1242	for (i = 0; i < pcie->nports; i++) {
1243		struct mvebu_pcie_port *port = pcie->ports + i;
1244		if (!port->base)
1245			continue;
1246		mvebu_writel(port, port->saved_pcie_stat, PCIE_STAT_OFF);
1247		mvebu_pcie_setup_hw(port);
1248	}
1249
1250	return 0;
1251}
1252
1253static void mvebu_pcie_port_clk_put(void *data)
1254{
1255	struct mvebu_pcie_port *port = data;
1256
1257	clk_put(port->clk);
1258}
1259
1260static int mvebu_pcie_parse_port(struct mvebu_pcie *pcie,
1261	struct mvebu_pcie_port *port, struct device_node *child)
1262{
1263	struct device *dev = &pcie->pdev->dev;
1264	u32 slot_power_limit;
1265	int ret;
1266	u32 num_lanes;
1267
1268	port->pcie = pcie;
1269
1270	if (of_property_read_u32(child, "marvell,pcie-port", &port->port)) {
1271		dev_warn(dev, "ignoring %pOF, missing pcie-port property\n",
1272			 child);
1273		goto skip;
1274	}
1275
1276	if (of_property_read_u32(child, "marvell,pcie-lane", &port->lane))
1277		port->lane = 0;
1278
1279	if (!of_property_read_u32(child, "num-lanes", &num_lanes) && num_lanes == 4)
1280		port->is_x4 = true;
1281
1282	port->name = devm_kasprintf(dev, GFP_KERNEL, "pcie%d.%d", port->port,
1283				    port->lane);
1284	if (!port->name) {
1285		ret = -ENOMEM;
1286		goto err;
1287	}
1288
1289	port->devfn = of_pci_get_devfn(child);
1290	if (port->devfn < 0)
1291		goto skip;
1292	if (PCI_FUNC(port->devfn) != 0) {
1293		dev_err(dev, "%s: invalid function number, must be zero\n",
1294			port->name);
1295		goto skip;
1296	}
1297
1298	ret = mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_MEM,
1299				 &port->mem_target, &port->mem_attr);
1300	if (ret < 0) {
1301		dev_err(dev, "%s: cannot get tgt/attr for mem window\n",
1302			port->name);
1303		goto skip;
1304	}
1305
1306	if (resource_size(&pcie->io) != 0) {
1307		mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_IO,
1308				   &port->io_target, &port->io_attr);
1309	} else {
1310		port->io_target = -1;
1311		port->io_attr = -1;
1312	}
1313
1314	/*
1315	 * Old DT bindings do not contain "intx" interrupt
1316	 * so do not fail probing driver when interrupt does not exist.
1317	 */
1318	port->intx_irq = of_irq_get_byname(child, "intx");
1319	if (port->intx_irq == -EPROBE_DEFER) {
1320		ret = port->intx_irq;
1321		goto err;
1322	}
1323	if (port->intx_irq <= 0) {
1324		dev_warn(dev, "%s: legacy INTx interrupts cannot be masked individually, "
1325			      "%pOF does not contain intx interrupt\n",
1326			 port->name, child);
1327	}
1328
1329	port->reset_name = devm_kasprintf(dev, GFP_KERNEL, "%s-reset",
1330					  port->name);
1331	if (!port->reset_name) {
1332		ret = -ENOMEM;
1333		goto err;
1334	}
1335
1336	port->reset_gpio = devm_fwnode_gpiod_get(dev, of_fwnode_handle(child),
1337						 "reset", GPIOD_OUT_HIGH,
1338						 port->name);
1339	ret = PTR_ERR_OR_ZERO(port->reset_gpio);
1340	if (ret) {
1341		if (ret != -ENOENT)
1342			goto err;
1343		/* reset gpio is optional */
1344		port->reset_gpio = NULL;
1345		devm_kfree(dev, port->reset_name);
1346		port->reset_name = NULL;
1347	}
1348
1349	slot_power_limit = of_pci_get_slot_power_limit(child,
1350				&port->slot_power_limit_value,
1351				&port->slot_power_limit_scale);
1352	if (slot_power_limit)
1353		dev_info(dev, "%s: Slot power limit %u.%uW\n",
1354			 port->name,
1355			 slot_power_limit / 1000,
1356			 (slot_power_limit / 100) % 10);
1357
1358	port->clk = of_clk_get_by_name(child, NULL);
1359	if (IS_ERR(port->clk)) {
1360		dev_err(dev, "%s: cannot get clock\n", port->name);
1361		goto skip;
1362	}
1363
1364	ret = devm_add_action(dev, mvebu_pcie_port_clk_put, port);
1365	if (ret < 0) {
1366		clk_put(port->clk);
1367		goto err;
1368	}
1369
1370	return 1;
1371
1372skip:
1373	ret = 0;
1374
1375	/* In the case of skipping, we need to free these */
1376	devm_kfree(dev, port->reset_name);
1377	port->reset_name = NULL;
1378	devm_kfree(dev, port->name);
1379	port->name = NULL;
1380
1381err:
1382	return ret;
1383}
1384
1385/*
1386 * Power up a PCIe port.  PCIe requires the refclk to be stable for 100µs
1387 * prior to releasing PERST.  See table 2-4 in section 2.6.2 AC Specifications
1388 * of the PCI Express Card Electromechanical Specification, 1.1.
1389 */
1390static int mvebu_pcie_powerup(struct mvebu_pcie_port *port)
1391{
1392	int ret;
1393
1394	ret = clk_prepare_enable(port->clk);
1395	if (ret < 0)
1396		return ret;
1397
1398	if (port->reset_gpio) {
1399		u32 reset_udelay = PCI_PM_D3COLD_WAIT * 1000;
1400
1401		of_property_read_u32(port->dn, "reset-delay-us",
1402				     &reset_udelay);
1403
1404		udelay(100);
1405
1406		gpiod_set_value_cansleep(port->reset_gpio, 0);
1407		msleep(reset_udelay / 1000);
1408	}
1409
1410	return 0;
1411}
1412
1413/*
1414 * Power down a PCIe port.  Strictly, PCIe requires us to place the card
1415 * in D3hot state before asserting PERST#.
1416 */
1417static void mvebu_pcie_powerdown(struct mvebu_pcie_port *port)
1418{
1419	gpiod_set_value_cansleep(port->reset_gpio, 1);
1420
1421	clk_disable_unprepare(port->clk);
1422}
1423
1424/*
1425 * devm_of_pci_get_host_bridge_resources() only sets up translateable resources,
1426 * so we need extra resource setup parsing our special DT properties encoding
1427 * the MEM and IO apertures.
1428 */
1429static int mvebu_pcie_parse_request_resources(struct mvebu_pcie *pcie)
1430{
1431	struct device *dev = &pcie->pdev->dev;
1432	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
1433	int ret;
1434
1435	/* Get the PCIe memory aperture */
1436	mvebu_mbus_get_pcie_mem_aperture(&pcie->mem);
1437	if (resource_size(&pcie->mem) == 0) {
1438		dev_err(dev, "invalid memory aperture size\n");
1439		return -EINVAL;
1440	}
1441
1442	pcie->mem.name = "PCI MEM";
1443	pci_add_resource(&bridge->windows, &pcie->mem);
1444	ret = devm_request_resource(dev, &iomem_resource, &pcie->mem);
1445	if (ret)
1446		return ret;
1447
1448	/* Get the PCIe IO aperture */
1449	mvebu_mbus_get_pcie_io_aperture(&pcie->io);
1450
1451	if (resource_size(&pcie->io) != 0) {
1452		pcie->realio.flags = pcie->io.flags;
1453		pcie->realio.start = PCIBIOS_MIN_IO;
1454		pcie->realio.end = min_t(resource_size_t,
1455					 IO_SPACE_LIMIT - SZ_64K,
1456					 resource_size(&pcie->io) - 1);
1457		pcie->realio.name = "PCI I/O";
1458
1459		ret = devm_pci_remap_iospace(dev, &pcie->realio, pcie->io.start);
1460		if (ret)
1461			return ret;
1462
1463		pci_add_resource(&bridge->windows, &pcie->realio);
1464		ret = devm_request_resource(dev, &ioport_resource, &pcie->realio);
1465		if (ret)
1466			return ret;
1467	}
1468
1469	return 0;
1470}
1471
1472static int mvebu_pcie_probe(struct platform_device *pdev)
1473{
1474	struct device *dev = &pdev->dev;
1475	struct mvebu_pcie *pcie;
1476	struct pci_host_bridge *bridge;
1477	struct device_node *np = dev->of_node;
1478	struct device_node *child;
1479	int num, i, ret;
1480
1481	bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct mvebu_pcie));
1482	if (!bridge)
1483		return -ENOMEM;
1484
1485	pcie = pci_host_bridge_priv(bridge);
1486	pcie->pdev = pdev;
1487	platform_set_drvdata(pdev, pcie);
1488
1489	ret = mvebu_pcie_parse_request_resources(pcie);
1490	if (ret)
1491		return ret;
1492
1493	num = of_get_available_child_count(np);
1494
1495	pcie->ports = devm_kcalloc(dev, num, sizeof(*pcie->ports), GFP_KERNEL);
1496	if (!pcie->ports)
1497		return -ENOMEM;
1498
1499	i = 0;
1500	for_each_available_child_of_node(np, child) {
1501		struct mvebu_pcie_port *port = &pcie->ports[i];
1502
1503		ret = mvebu_pcie_parse_port(pcie, port, child);
1504		if (ret < 0) {
1505			of_node_put(child);
1506			return ret;
1507		} else if (ret == 0) {
1508			continue;
1509		}
1510
1511		port->dn = child;
1512		i++;
1513	}
1514	pcie->nports = i;
1515
1516	for (i = 0; i < pcie->nports; i++) {
1517		struct mvebu_pcie_port *port = &pcie->ports[i];
1518		int irq = port->intx_irq;
1519
1520		child = port->dn;
1521		if (!child)
1522			continue;
1523
1524		ret = mvebu_pcie_powerup(port);
1525		if (ret < 0)
1526			continue;
1527
1528		port->base = mvebu_pcie_map_registers(pdev, child, port);
1529		if (IS_ERR(port->base)) {
1530			dev_err(dev, "%s: cannot map registers\n", port->name);
1531			port->base = NULL;
1532			mvebu_pcie_powerdown(port);
1533			continue;
1534		}
1535
1536		ret = mvebu_pci_bridge_emul_init(port);
1537		if (ret < 0) {
1538			dev_err(dev, "%s: cannot init emulated bridge\n",
1539				port->name);
1540			devm_iounmap(dev, port->base);
1541			port->base = NULL;
1542			mvebu_pcie_powerdown(port);
1543			continue;
1544		}
1545
1546		if (irq > 0) {
1547			ret = mvebu_pcie_init_irq_domain(port);
1548			if (ret) {
1549				dev_err(dev, "%s: cannot init irq domain\n",
1550					port->name);
1551				pci_bridge_emul_cleanup(&port->bridge);
1552				devm_iounmap(dev, port->base);
1553				port->base = NULL;
1554				mvebu_pcie_powerdown(port);
1555				continue;
1556			}
1557			irq_set_chained_handler_and_data(irq,
1558							 mvebu_pcie_irq_handler,
1559							 port);
1560		}
1561
1562		/*
1563		 * PCIe topology exported by mvebu hw is quite complicated. In
1564		 * reality has something like N fully independent host bridges
1565		 * where each host bridge has one PCIe Root Port (which acts as
1566		 * PCI Bridge device). Each host bridge has its own independent
1567		 * internal registers, independent access to PCI config space,
1568		 * independent interrupt lines, independent window and memory
1569		 * access configuration. But additionally there is some kind of
1570		 * peer-to-peer support between PCIe devices behind different
1571		 * host bridges limited just to forwarding of memory and I/O
1572		 * transactions (forwarding of error messages and config cycles
1573		 * is not supported). So we could say there are N independent
1574		 * PCIe Root Complexes.
1575		 *
1576		 * For this kind of setup DT should have been structured into
1577		 * N independent PCIe controllers / host bridges. But instead
1578		 * structure in past was defined to put PCIe Root Ports of all
1579		 * host bridges into one bus zero, like in classic multi-port
1580		 * Root Complex setup with just one host bridge.
1581		 *
1582		 * This means that pci-mvebu.c driver provides "virtual" bus 0
1583		 * on which registers all PCIe Root Ports (PCI Bridge devices)
1584		 * specified in DT by their BDF addresses and virtually routes
1585		 * PCI config access of each PCI bridge device to specific PCIe
1586		 * host bridge.
1587		 *
1588		 * Normally PCI Bridge should choose between Type 0 and Type 1
1589		 * config requests based on primary and secondary bus numbers
1590		 * configured on the bridge itself. But because mvebu PCI Bridge
1591		 * does not have registers for primary and secondary bus numbers
1592		 * in its config space, it determinates type of config requests
1593		 * via its own custom way.
1594		 *
1595		 * There are two options how mvebu determinate type of config
1596		 * request.
1597		 *
1598		 * 1. If Secondary Bus Number Enable bit is not set or is not
1599		 * available (applies for pre-XP PCIe controllers) then Type 0
1600		 * is used if target bus number equals Local Bus Number (bits
1601		 * [15:8] in register 0x1a04) and target device number differs
1602		 * from Local Device Number (bits [20:16] in register 0x1a04).
1603		 * Type 1 is used if target bus number differs from Local Bus
1604		 * Number. And when target bus number equals Local Bus Number
1605		 * and target device equals Local Device Number then request is
1606		 * routed to Local PCI Bridge (PCIe Root Port).
1607		 *
1608		 * 2. If Secondary Bus Number Enable bit is set (bit 7 in
1609		 * register 0x1a2c) then mvebu hw determinate type of config
1610		 * request like compliant PCI Bridge based on primary bus number
1611		 * which is configured via Local Bus Number (bits [15:8] in
1612		 * register 0x1a04) and secondary bus number which is configured
1613		 * via Secondary Bus Number (bits [7:0] in register 0x1a2c).
1614		 * Local PCI Bridge (PCIe Root Port) is available on primary bus
1615		 * as device with Local Device Number (bits [20:16] in register
1616		 * 0x1a04).
1617		 *
1618		 * Secondary Bus Number Enable bit is disabled by default and
1619		 * option 2. is not available on pre-XP PCIe controllers. Hence
1620		 * this driver always use option 1.
1621		 *
1622		 * Basically it means that primary and secondary buses shares
1623		 * one virtual number configured via Local Bus Number bits and
1624		 * Local Device Number bits determinates if accessing primary
1625		 * or secondary bus. Set Local Device Number to 1 and redirect
1626		 * all writes of PCI Bridge Secondary Bus Number register to
1627		 * Local Bus Number (bits [15:8] in register 0x1a04).
1628		 *
1629		 * So when accessing devices on buses behind secondary bus
1630		 * number it would work correctly. And also when accessing
1631		 * device 0 at secondary bus number via config space would be
1632		 * correctly routed to secondary bus. Due to issues described
1633		 * in mvebu_pcie_setup_hw(), PCI Bridges at primary bus (zero)
1634		 * are not accessed directly via PCI config space but rarher
1635		 * indirectly via kernel emulated PCI bridge driver.
1636		 */
1637		mvebu_pcie_setup_hw(port);
1638		mvebu_pcie_set_local_dev_nr(port, 1);
1639		mvebu_pcie_set_local_bus_nr(port, 0);
1640	}
1641
1642	bridge->sysdata = pcie;
1643	bridge->ops = &mvebu_pcie_ops;
1644	bridge->child_ops = &mvebu_pcie_child_ops;
1645	bridge->align_resource = mvebu_pcie_align_resource;
1646	bridge->map_irq = mvebu_pcie_map_irq;
1647
1648	return pci_host_probe(bridge);
1649}
1650
1651static void mvebu_pcie_remove(struct platform_device *pdev)
1652{
1653	struct mvebu_pcie *pcie = platform_get_drvdata(pdev);
1654	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
1655	u32 cmd, sspl;
1656	int i;
1657
1658	/* Remove PCI bus with all devices. */
1659	pci_lock_rescan_remove();
1660	pci_stop_root_bus(bridge->bus);
1661	pci_remove_root_bus(bridge->bus);
1662	pci_unlock_rescan_remove();
1663
1664	for (i = 0; i < pcie->nports; i++) {
1665		struct mvebu_pcie_port *port = &pcie->ports[i];
1666		int irq = port->intx_irq;
1667
1668		if (!port->base)
1669			continue;
1670
1671		/* Disable Root Bridge I/O space, memory space and bus mastering. */
1672		cmd = mvebu_readl(port, PCIE_CMD_OFF);
1673		cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
1674		mvebu_writel(port, cmd, PCIE_CMD_OFF);
1675
1676		/* Mask all interrupt sources. */
1677		mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF);
1678
1679		/* Clear all interrupt causes. */
1680		mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF);
1681
1682		if (irq > 0)
1683			irq_set_chained_handler_and_data(irq, NULL, NULL);
1684
1685		/* Remove IRQ domains. */
1686		if (port->intx_irq_domain)
1687			irq_domain_remove(port->intx_irq_domain);
1688
1689		/* Free config space for emulated root bridge. */
1690		pci_bridge_emul_cleanup(&port->bridge);
1691
1692		/* Disable sending Set_Slot_Power_Limit PCIe Message. */
1693		sspl = mvebu_readl(port, PCIE_SSPL_OFF);
1694		sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE);
1695		mvebu_writel(port, sspl, PCIE_SSPL_OFF);
1696
1697		/* Disable and clear BARs and windows. */
1698		mvebu_pcie_disable_wins(port);
1699
1700		/* Delete PCIe IO and MEM windows. */
1701		if (port->iowin.size)
1702			mvebu_pcie_del_windows(port, port->iowin.base, port->iowin.size);
1703		if (port->memwin.size)
1704			mvebu_pcie_del_windows(port, port->memwin.base, port->memwin.size);
1705
1706		/* Power down card and disable clocks. Must be the last step. */
1707		mvebu_pcie_powerdown(port);
1708	}
1709}
1710
1711static const struct of_device_id mvebu_pcie_of_match_table[] = {
1712	{ .compatible = "marvell,armada-xp-pcie", },
1713	{ .compatible = "marvell,armada-370-pcie", },
1714	{ .compatible = "marvell,dove-pcie", },
1715	{ .compatible = "marvell,kirkwood-pcie", },
1716	{},
1717};
1718
1719static const struct dev_pm_ops mvebu_pcie_pm_ops = {
1720	NOIRQ_SYSTEM_SLEEP_PM_OPS(mvebu_pcie_suspend, mvebu_pcie_resume)
1721};
1722
1723static struct platform_driver mvebu_pcie_driver = {
1724	.driver = {
1725		.name = "mvebu-pcie",
1726		.of_match_table = mvebu_pcie_of_match_table,
1727		.pm = &mvebu_pcie_pm_ops,
1728	},
1729	.probe = mvebu_pcie_probe,
1730	.remove_new = mvebu_pcie_remove,
1731};
1732module_platform_driver(mvebu_pcie_driver);
1733
1734MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@bootlin.com>");
1735MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
1736MODULE_DESCRIPTION("Marvell EBU PCIe controller");
1737MODULE_LICENSE("GPL v2");
1738